Rearrangement of lard



United States Patent 3,392,031 REARRANGEMENT 0F LARD John E. Thompson,908 Burns Ave, Flossmoor, Ill. 60422 No Drawing. Continuation-impart ofapplication Ser. No. 202,396, .inne 14, 1962. This application Aug. 4,1964, Ser. No. 387,514

3 Claims. (Cl. 99-118) ABSTRACT OF THE DISCLOSURE Lard containing 0.025to 0.1% water is interesterified in the presence of an anhydrousdehydrating salt, sodium or magnesium sulfate, using a reduced amount ofcatalyst.

This application is a continuation-in-part of applicants priorapplication S.N. 202,396, filed June 14, 1962, which has been abandonedin favor of this application.

This invention relates to the rearrangement of lard with metalalcoholates and more in particular it relates to an improvement in thewell known rearrangement process comprising a method of removing waterfrom the lard.

Heretofore, it has been the practice to vacuum dry lard or other fats oroils before rearrangement. If there is a small amount of moisturepresent in the lard, in the neighborhood of 0.025% to 0.1%, the lard maybe rearranged using an excess of sodium methoxide, the excess reactingwith the water which leads to undesirable results, because sodiummethoxide is expensive and increases the cost of the process and alsothe hydrolysis product of sodium methoxide leads to the production ofsoap which can cause an emulsion to form during the process, whichemulsion is highly undesirable.

Modified lard has been produced by treating lard with metal alcoholateswhich comprise treating the anhydrous lard, usually vacuum flash dried,with sodium methoxide or its equivalent material at a temperaturebetween that necessary to keep the lard in liquid phase and at about 50C. This process is clearly set forth in the Vander Wal et al. Patent No.Re. 23,499, the Holman et al. Patent No. 2,875,066 and in the VanAklreren Patent No. 2,872,463.

It is an object of the present invention to provide a method ofdehydrating lard prior to metal alcoholate rearrangement.

It is also an object of the present invention to provide a dehydratingprocess that is simple in its operation and does not require expensiveequipment.

It is a further object of the invention to provide a material that whenadded to the lard will remove the water therefrom in such a manner asnot to interfere with the alkali metal rearrangement.

It is a still further object of this invention to provide a dehydratingmaterial that when added to the lard will be soluble in, and that can beremoved by, the water that is added to terminate the rearrangementreaction.

The various features of novelty which characterize this invention arepointed out with particularity in the claims annexed to and forming partof this specification. For a better understanding of the invention,however, its advantages and specific objects obtained by its use,reference should be had to the various examples and descriptive matterin which have been presented a preferred embodiment of the invention.

Lard was rearrangement using sodium methoxide or metallic sodium as thecatalyst. The lard was collected directly from the manufacturing processat a temperature of 120 C. to 150 C. It was allowed to cool to 50 C. andcontained 0.1% water. Fresh sodium methoxide Patented July 9, 1968 ormetallic sodium dispersions were used to ensure optimum results.

Anhydrous sodium sulphate was heated at C. for 2 hours prior to use. Allof the rearrangement reactions were run for 1 hour with agitation at 50C. and then the sodium methoxide or the metallic sodium, and the sodiumsulphate were removed by adding water.

The congeal point and diflferential cooling curves are excellentindicators of the extent of the rearrangement. A congeal point of lessthan 3 C. is considered to be satisfactory. The diiferential coolingcurves are referred by Wiedmann et al., Journal of the American OilChemists Society, vol. 38, pp. 389-395 (1961).

In the following examples 500 parts of lard were used in all of thereactions.

Example 1 With 500 parts of lard 3.96 parts of sodium methoxide wereadded. 1.45 parts were used to neutralize the water and 2.5 or 0.5% wereused to catalyze the reaction. After 1 hour the reaction was terminatedby adding 20 parts of water.

Example 2 2.29 parts of sodium methoxide were added to 500 parts oflard. 1.46 parts were used to neutralize the water and 0.83 part or0.17% were used to catalyze the reaction. After 1 hour the reaction wasterminated by adding 20 parts of water.

Example 3 10 parts of anhydrous sodium sulphate were added to 500 partsof lard, mixed for 10 minutes and filtered. 2.29 parts of sodiummethoxide were added, as in Example 2. After 1 hour the reaction wasterminated by adding 20 parts of water.

Example 4 To 500 parts of lard, containing 0.025 to 0.1 part of water,10 parts of anhydrous sodium sulphate were mixed for 10 minutes, then 2parts of metallic sodiumfinely dispersedin lard were added as arearrangement catalyst. After one hour the reaction was terminated byadding 20 parts of water.

The results are presented in the following table:

Amount Amount; Amount of Amount of Congeal of lard, of H20 NazSO NaOMeor Point, parts parts parts Na, parts C Undcodorized er 16. 6 DeodorizedLard. 14. 4

While in the above examples anhydrous sodium sulphate was used as adehydrating agent, other materials may be used, such as magnesiumsulphate. These dehydrating agents must be so inert that they may remainin the reaction chamber during the rearrangement and they must be easilyremoved, preferably as a solution with the Water or dilute acid, that isadded to terminate the rearrrangement reaction. They must be effectiveat the temperature necessary to maintain the fatty material in a moltencondition, that is 105 F., or higher. The dehydrating agent must not becapable of promoting an undesirable reaction, such as copper sulphate,which is a powerful pro-oxidant, which promotes rancidity at a level ofone part per billion. They must not be reactive with the lard, such assodium hydroxide, which would promote hydrolysis. The dehydrating agentmust not be toxic or dangerous as would phosphorus pentoxide orconcentrated sulfuric acid and must not be reactive with a metallicmethoxide catalyst, thus eliminating any of the acid materials. Calciumchloride is not sufficiently active at the temperature of the reactionto remove the water, that is calcium chloride does not have a greaterafiinity for the water than does the metallic methoxide catalyst. Silicagel is not water soluble so that it may be removed from the solution.

While in the above examples sodium methoxide was used as a catalyst,other metal salts of an alcohol, containing less than carbon atoms andless than 3 hydroxy groups may be used. The preferred material is analkali metal salt of a monohydroxy alkane of which sodium methoxide isthe material used in Examples 1 to 4. Metallic sodium dispersions mayalso be used for the interesterification or rearrangement reaction.Example 5 uses two parts of metallic sodium.

The use of at least 2% of a solid dehydrating agent that is watersoluble as set forth above, has the advantage of greatly reducing thequantity of the sodium methoxide catalyst needed for completerearrangement. No filtering is necessary prior to adding the catalystand the use of water to terminate the reaction removes both the catalystand the dehydrating agent. Of course, the use of a solid catalystselected from the group consisting of an alkali metal dispersion and analkali metal salt of an alcohol containing less than 5 carbon atoms andless than three hydroxy groups,

(c) heating the mixture to a temperature of at least C. for a length oftime sufficient to produce the rearrangement,

(d) terminating the reaction by the addition of Water thereto, and

(e) removing the solution of anhydrous salt, the Water and thedecomposition products of the alkali metal catalyst. 2. The process ofclaim 1, wherein said dehydrating salt is anhydrous sodium sulphate.

3. The process of claim 1, wherein said dehydrating salt is anhydrousmagnesium sulphate.

References Cited UNITED STATES PATENTS 2,614,937 10/1952 Baur et a1.99118 2,727,913 12/1955 Kuhrt et a1. 260410.7 2,875,066 2/1959 Holman etal 260410.7

MAURICE W. GREENSTEIN, Primary Examiner.

HENRY R. JILES, Examiner.

